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  <title>绝对值</title>
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 <body class="docs"><div id="layout">
  <div id="layout-content"><div id="function.abs" class="refentry">
   <div class="refnamediv">
    <h1 class="refname">abs</h1>
    <p class="verinfo">(PHP 4, PHP 5, PHP 7)</p><p class="refpurpose"><span class="refname">abs</span> &mdash; <span class="dc-title">绝对值</span></p>

   </div>
 <div class="refsect1 description" id="refsect1-function.abs-description">
  <h3 class="title">说明</h3>
   <div class="methodsynopsis dc-description">
    <span class="methodname"><strong>abs</strong></span>
     ( <span class="methodparam"><span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <code class="parameter">$number</code></span>
    ) : <span class="type"><a href="language.pseudo-types.html#language.types.number" class="type number">number</a></span></div>

    <p class="para rdfs-comment">
     返回参数 <code class="parameter">number</code> 的绝对值。
    </p>
   </div>

   
   <div class="refsect1 parameters" id="refsect1-function.abs-parameters">
  <h3 class="title">参数</h3>
  <p class="para">
   <dl>

    
     <dt>
<code class="parameter">number</code></dt>

     <dd>

      <p class="para">
       要处理的数字值
      </p>
     </dd>

    
   </dl>

  </p>
 </div>

 <div class="refsect1 returnvalues" id="refsect1-function.abs-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
   <code class="parameter">number</code> 的绝对值。 如果参数 <code class="parameter">number</code>
     是 <span class="type"><a href="language.types.float.html" class="type float">float</a></span>，则返回的类型也是 <span class="type"><a href="language.types.float.html" class="type float">float</a></span>，否则返回
     <span class="type"><a href="language.types.integer.html" class="type integer">integer</a></span>（因为 <span class="type"><a href="language.types.float.html" class="type float">float</a></span> 通常比 <span class="type"><a href="language.types.integer.html" class="type integer">integer</a></span> 有更大的取值范围）。
  </p>
 </div>

 <div class="refsect1 examples" id="refsect1-function.abs-examples">
  <h3 class="title">范例</h3>
  <p class="para">
   <div class="example" id="example-4115">
    <p><strong>Example #1 <span class="function"><strong>abs()</strong></span> 例子</strong></p>
    <div class="example-contents">
<div class="phpcode"><pre><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$abs&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">abs</span><span style="color: #007700">(-</span><span style="color: #0000BB">4.2</span><span style="color: #007700">);&nbsp;</span><span style="color: #FF8000">//&nbsp;$abs&nbsp;=&nbsp;4.2;&nbsp;(double/float)<br /></span><span style="color: #0000BB">$abs2&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">abs</span><span style="color: #007700">(</span><span style="color: #0000BB">5</span><span style="color: #007700">);&nbsp;&nbsp;&nbsp;</span><span style="color: #FF8000">//&nbsp;$abs2&nbsp;=&nbsp;5;&nbsp;(integer)<br /></span><span style="color: #0000BB">$abs3&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">abs</span><span style="color: #007700">(-</span><span style="color: #0000BB">5</span><span style="color: #007700">);&nbsp;&nbsp;</span><span style="color: #FF8000">//&nbsp;$abs3&nbsp;=&nbsp;5;&nbsp;(integer)<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</pre></div>
    </div>

   </div>
  </p>
 </div>


 <div class="refsect1 seealso" id="refsect1-function.abs-seealso">
  <h3 class="title">参见</h3>
  <p class="para">
   <ul class="simplelist">
    <li class="member"><span class="function"><a href="gmp_abs.html" class="function" rel="rdfs-seeAlso">gmp_abs()</a> - Absolute value</span></li>
    <li class="member"><span class="function"><a href="gmp_sign.html" class="function" rel="rdfs-seeAlso">gmp_sign()</a> - Sign of number</span></li>
   </ul>
  </p>
 </div>


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